OPA820ID - Low-Noise Unity-Stable Op Amp | Texas Instruments
Référence : OPA820ID ✓ ActifOPA820ID Présentation
An operational amplifier is a voltage-gain element that uses differential feedback to amplify the voltage difference between its inverting and non-inverting inputs. The OPA820 belongs to the voltage-feedback operational amplifier family, where feedback sets the closed-loop gain. Voltage-feedback amplifiers are commonly used in sensor conditioning, test equipment, communications, imaging, and precision measurement because they provide predictable bandwidth behavior and straightforward external compensation.
The OPA820's defining characteristics include its low-noise design, unity-gain stability, voltage-feedback topology, single-amplifier configuration, and low 5.6 mA supply current. Unity-gain stability allows the amplifier to operate as a buffer without requiring an added compensation network. This simplifies low-level signal paths where source impedance can make the amplifier input noise, bias current, and offset-voltage behavior important.
OPA820ID is packaged in the standard 8-pin SOIC surface-mount format. Its compact outline supports conventional PCB assembly while exposing separate supply, input, and output connections. When evaluating a complete amplifier design, consult the manufacturer datasheet for gain-bandwidth product, slew rate, input-noise density, input offset voltage, input bias current, output-current capability, common-mode range, and supply-voltage limits.
Typical uses include low-level sensor amplification, photodiode signal chains, high-speed instrumentation, communications interfaces, active filtering, and precision measurement equipment. In these applications, low input noise helps preserve weak signals, while the voltage-feedback architecture supports controlled gain and bandwidth. The unity-gain-stable configuration is particularly useful in buffers and follower stages placed close to sensitive sources.
For reliable performance, place the amplifier close to the signal source, keep feedback traces short, and use decoupling capacitors according to the manufacturer datasheet. Check output swing, slew-rate limits, and load capability before driving downstream circuitry. Stable operation also depends on maintaining the specified supply voltage and avoiding excessive capacitive loading at the output.
This page combines manufacturer-device identification, verified distributor listings, application guidance, pin and package information, and engineering design notes to support component selection and PCB implementation. The OPA820ID datasheet is the controlling technical reference for electrical limits, test conditions, typical performance curves, package dimensions, and recommended application circuits.
Alternatives de remplacement direct pour OPA820ID — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Aucune alternative de remplacement direct disponible pour ce produit.
Demander des alternativesOPA820ID Valeurs maximales et caractéristiques électriques
| Amplifier Type | Voltage-feedback operational amplifier |
| Number of Circuits | 1 circuit |
| Gain Configuration | Unity-gain stable |
| Noise Class | Low-noise |
| Courant d'alimentation | 5.6 mA |
| Boîtier | 8-pin SOIC |
| Type de montage | Surface mount |
Guide de configuration des broches du OPA820ID 8-pin soic
Configuration des broches du OPA820ID (boîtier 8-pin soic). Ce composant analogique comporte des broches d'entrée, de sortie et d'alimentation. Consultez la fiche technique du fabricant pour les configurations des broches d'annulation d'offset, de compensation et d'activation. Idéal pour le conditionnement de signaux et les circuits amplificateurs.
Aucune donnée de brochage détaillée disponible pour OPA820ID.
Consultez la fiche technique pour la configuration complète des broches.
Applications typiques
OPA820ID convient pour 6 applications: Low-Level Sensor Signal Conditioning, Precision Buffer and Follower, Test and Measurement Instrumentation, Communications and RF Baseband, Active Filtering, Data Acquisition Front End.
Low-Level Sensor Signal Conditioning
OPA820ID fits sensor-amplifier front ends that must preserve small differential signals while adding gain and driving a sampling or conversion stage. Its low-noise voltage-feedback architecture is appropriate when source impedance makes input-referred noise important, while unity-gain stability permits direct buffering without an added compensation network. The stated 5.6 mA supply current also limits the contribution of each active channel to a multichannel acquisition system. Confirm the sensor output range against the input common-mode limits and verify offset, bias-current, output-swing, and noise-density requirements in the manufacturer datasheet.
Recommandé
Precision Buffer and Follower
OPA820ID can serve as a unity-gain buffer when a sensor or high-impedance source must be isolated from a lower-impedance downstream circuit. Unity-gain stability is the central advantage because it allows voltage-feedback operation at a gain of one without a compensation network. The low-noise design helps preserve the source signal, and the 5.6 mA supply current is useful when channel count or battery capacity is constrained. Check input bias current, offset voltage, capacitive-load stability, output swing, and load-current limits for the exact source impedance and supply rails.
Recommandé
Test and Measurement Instrumentation
OPA820ID is well matched to instrumentation paths where a low-level source must be amplified accurately before reaching an ADC, attenuator, or analysis block. The unity-gain-stable, low-noise voltage-feedback design supports gain stages and buffers without introducing stability-compensation complexity. Its 5.6 mA supply current can simplify thermal and power planning in multichannel instruments. Validate the gain-bandwidth product, slew rate, settling behavior, common-mode range, and output-current capability against the measurement bandwidth and required step response.
Recommandé
Communications and RF Baseband
OPA820ID can be used in low-level communications and RF baseband circuitry where the amplifier must combine low noise with predictable voltage-feedback behavior. Its unity-gain stability allows it to buffer mixer or detector outputs, and the compact 8-pin SOIC supports placement close to the source. For IF or wideband paths, compare the amplifier's gain-bandwidth product, slew rate, input noise, and output-voltage swing with the operating frequency and channel bandwidth. Account for parasitic capacitance and ensure the feedback network remains stable under the intended capacitive load.
Recommandé
Active Filtering
OPA820ID can implement active analog filters where low-noise amplification and stable feedback behavior are required around a signal band. Its voltage-feedback architecture supports conventional inverting and noninverting filter topologies, while unity-gain stability permits buffer sections without added compensation. At higher frequencies, verify the gain-bandwidth product and slew rate so that the closed-loop filter response retains the intended shape. Component tolerances, parasitic capacitance, and output loading can also affect the realized response and should be checked against the manufacturer's test and application guidance.
Recommandé
Data Acquisition Front End
OPA820ID fits a data-acquisition front end that must amplify a sensor or conditioning-network output before conversion. Low input noise helps reduce errors referred to the original signal, and unity-gain stability provides flexibility for input buffers and first gain stages. The 5.6 mA supply current supports power-conscious multi-channel implementations. Establish the usable input range, common-mode limits, gain error, offset, bandwidth, and output drive requirements for the selected ADC, then include the amplifier's settling behavior and PCB leakage in the overall acquisition error budget.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour OPA820ID — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit |
|---|---|
| Brand | Texas Instruments |
| Package | 8-pin SOIC |
| Amplifier Type | Voltage-feedback operational amplifier |
| Number of Circuits | 1 circuit |
| Gain Stability | Unity-gain stable |
| Supply Current | 5.6 mA |
| Noise Class | Low-noise |
Principaux différenciateurs
- Direct unity-gain buffering (vs OPA875ID)
- Low-noise voltage-feedback signal path (vs OPA875ID)
- Compact standard package (vs OPA132UA)
Notes de conception
Place OPA820ID near the source of the signal and keep the inverting feedback route short and compact. Sensitive input and feedback nodes should remain away from switching nodes, high-current returns, and digital timing signals. Use a continuous ground reference beneath the analog section and route return currents directly to the relevant supply or ground structure rather than through long shared traces.
Provide local supply decoupling according to the Texas Instruments OPA820 manufacturer datasheet and place the components close to the amplifier pins. Check both positive and negative supply requirements, including whether the device supports a ground-referenced single supply or requires a negative rail. Estimated: each active OPA820ID channel contributes 5.6 mA of supply current; multiply this value by the channel count and include the load current required by downstream circuitry.
Keep the feedback network physically small and terminate unused inputs according to the manufacturer guidance. Avoid adding large parasitic capacitance to the output unless the amplifier's output-capacitance limit is confirmed. For high-frequency operation, evaluate closed-loop bandwidth and slew rate together, because a circuit can meet the gain-bandwidth requirement while still failing the required large-signal settling time.
Do not assume that any 8-pin SOIC amplifier is a drop-in replacement. Verify pin numbering, input assignments, supply pins, common-mode range, output swing, offset, bias current, noise, bandwidth, and slew rate. Also distinguish the standard OPA820ID orderable configuration from tape-and-reel or other suffix variants when creating a replacement plan for production.
Informations de conformité
No explicit RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals status was identified for the exact OPA820ID configuration. Confirm the current declarations and material documentation for the ordered part before production release.